The invention relates to modifying video and audio.
When a video program is created at a nonlinear video editor, analog video source materials are typically digitized, compressed and stored on disc for later random access for use in creating a video program. Digital source video can also be input into the nonlinear video editor. Segments of the video, also referred to as “video clips,” can be taken from different sources, and the beginning and end points can be trimmed as desired during editing. The order of clips is established in a time line to determine the sequence, and the position of a clip can be changed. Clips can be deleted or inserted as desired. During the editing process, the clips of compressed video can be randomly accessed, decompressed and viewed in real time.
The source video can be modified by various “pixel manipulations,” which are fine grain processes (such as scale, rotate, blur), and “tools,” which are larger grain processes (such as digitizing, color correcting, add to timeline, layer with another clip and master out).
Audio can similarly be modified, e.g., by parametric equalization, high pass/low pass, notch filters.
Compositing involves use of fine grain processes. In compositing applications, it is known to use a process tree to specify a set of transformations, modifications, and effects to be applied to one clip. As used herein, “filter operations” includes operations by compositing and by tools.